NOTUNINGNONADA

Good morning Honda-tech,

The weirdest thing has happened to me and i have gone to my wits end to troubleshoot and still coming up dry....this is whats going on:

Car will start first thing in the morning, I can drive it with no problem but once i shut it off and leave it be for over 10 minutes...it does not want to start again...The first time it happened it did it at a gas station after i got gas.. and ever since then i have to wait apporx. 30-45 minutes between stops before i can crank it and it runs like there isnt any problem.

Things i have done:
changed fuel pump, changed fuel pressure regulator, checked for spark, new wires, plugs, new plugs, rotor and cap, cleaned out the distributor and replaced gasket ( i was in there so i figured why not)

Any help will do before i throw my hands up

Platform: JDM B18C no mods just a fast to an from work car

CandyRedRC46

Fuel Pump Relay?
Distributor:
Ignition Coil?
Ignition Igniter?

mk378

When it will not start, check for spark. Also check the CEL cycling on and off when you turn key on and don't crank, and the fuel pump priming.

You have to do this during that time when it will not start. Testing stuff when it will start anyway is going to show everything is normal.

NOTUNINGNONADA

Main relay clicks twice..fuel pump primes for 3-4 sec
Ignition coil...i stuck a screw driver and seen a spark but its day light cant tell if its weak or not
Igniter?!?! you mean the module inside the distributor?? havent pulled it out yet

NOTUNINGNONADA

Yes there is spark when turning over..but it looks weak...gonna wait til tonight and view it again

CEL comes on and off like it suppose to and matches with the fuel pump priming

NOTUNINGNONADA

UPDATE:

ok i got it to start after 3-4 tries first time it started it ran like it was on 2 cylinders but when i tried it again it started fine now im playing the waiting game..so far when i pulled into the yard it started right up..its been about 10 min since i let it sit i will give it another 15 min and try to start it...im thinking about doing a Seafoam clean to my car sic i haven dont it in over 3 years....

CandyRedRC46

Don't sea foam your car. That is a really shitty/lazy thing to do....
If you are going to try and clean your engine, just do it right.
​​​​​​​
Pull the Throttle Body/FITV/IACV off, soak them in Simple green, scrub/rinse/repeat a few times and reassemble and have your fuel injectors professionally cleaned/serviced (Ultrasonic cleaning).
(If you had a lot of time on your hands, which I don't think you do, I would pull the intake manifold and clean that out too)
But Seafoaming isn't the answer, you're just going to push all of the sludge in the Throttle Body/FITV/IACV/intake manifold further down and into your engine.
I know some people think the seafoam smoke show is cool, but that isn't good for your engine, you are just gunking up your valves/combustion chamber/ catalytic converter/exhaust/spark plugs/o2 sensor(s), MAP sensor/etc....

I don't know what the hell a screw driver test is, but there is a proper way to test the voltage and resistance of the ignition coil and igniter in the service manual, you should do that or if you are lazy and have $180 dollars to spare, just buy a new Rich Porter distributor and slap that on. I have one that is 2 years old and has been great so far. I think it is the most reliable of the aftermarket distributors.

I am not sure how confident I am in your fuel pump relay testing. Maybe Try swapping that out for a known good or new oem one, when you are having issues, to narrow down the variables.

​​​​​​​When you say that you already changed the wires/rotor/cap and plugs, were the spark plugs gapped correctly? Were the wires/rotor/cap new oem?

B18C5-EH2

TW/Coolant Temp sensor. It is the two-pin temp sensor under your distributor, NOT the one spade connector one (that's the temp sending unit that runs your temp gauge only.) This TW/Coolant Temp sensor is flooding your car after it gets hot because it's faulty. I've had this issue no less than five times spread across my various Hondas over the years. Most of the time it will throw a random-*** CEL, but not always.

Check for a check engine code 6. Refer to THIS CHART if you see other codes.

Trust me, swap this, and you're welcome.

P/N - 37870-PJ7-003

tamboo

a likely culprit but test with multimeter before removing.
pulled mine and couldnt get front block coolant plug out.
result was air in coolant system nightmare.
finally bought lisle funnel which resolved things but it was a lot of bs.

Megalodong

There's a 20 year Honda dealer mechanic (Ezone) on Civic Forums that will tell you otherwise: https://www.civicforums.com/forums/2...turn-over.html

mk378

To replace sensor without losing much coolant, wait until the engine is completely cold. Do NOT open the radiator cap. As the engine cools off, a slight vacuum forms which will help keep coolant from gushing out. Unscrew the sensor and slam in the new one right away.